666666667

Properties

Appears in sequences

• Primes that when squared gives numbers with digits in nondecreasing order.at n=26A028865
• a(n)^2 is smallest square starting with a string of n 4's.at n=8A034984
• Smallest n-digit prime containing only the digits 6 and 7, or 0 if no such prime exists.at n=8A036948
• Smallest prime containing exactly n 6's.at n=8A037065
• Numbers k such that k^2 contains only digits {4,8,9}.at n=19A053966
• Smallest prime beginning with exactly n 6's.at n=8A065589
• Number of Fibonacci numbers A000045(k), k <= 10^n, which end in 4.at n=10A067275
• Duplicate of A067275.at n=10A073552
• Smallest prime == 1 (mod n-th unary number U(n) = (10^n-1)/9).at n=8A083808
• Numbers n > 2 such that n divides the concatenation of n-2 and n-1.at n=10A088797
• Primes of the form identical digits followed by a 7.at n=23A090147
• Primes of the form 60*R_k + 7, where R_k is the repunit (A002275) of length k.at n=4A093170
• Primes of the form 1 + repdigit. Primes whose totient is a repdigit.at n=10A096505
• a(n) is the least prime following A002280[n] repdigits.at n=9A099660
• Near-repdigit primes with at least two 6's as the repeated digit.at n=4A105978
• Primes such that the outer 2 digits are n and n+1 and all inner digits are 6, where 0 < n < 9.at n=8A108823
• The n-digit prime with the largest number of 6's, the largest of these if there is more than 1. 0 if no such prime exists.at n=8A178004
• Smallest prime that does not divide at least one n-digit pandigital number.at n=3A228253
• k-digit primes with the same even digit repeated k-1 times and a single odd digit.at n=38A320256
• Primes p such that p^2 is the concatenation of x and 2*x+1 for some x.at n=8A355970